A team of Iowa State University plant scientists and materials chemists have successfully used nanotechnology to penetrate plant cell walls and simultaneously deliver a gene and a chemical that triggers its expression with controlled precision. Their breakthrough brings nanotechnology to plant biology and agricultural biotechnology, creating a powerful new tool for targeted delivery into plant cells.

The research, "Mesoporous Silica Nanoparticles Deliver DNA and Chemicals into Plants," is a highlighted article in the May issue of Nature Nanotechnology.

...."With the mesoporous nanoparticles, we can deliver two biogenic species at the same time," Wang said. "We can bring in a gene and induce it in a controlled manner at the same time and at the same location. That's never been done before."

The controlled release will improve the ability to study gene function in plants. And in the future, scientists could use the new technology to deliver imaging agents or chemicals inside cell walls. This would provide plant biologists with a window into intracellular events.

...."The team found a chemical we could use that made the nanoparticle look yummy to the plant cells so they would swallow the particles," Torney said.

It worked. The nanoparticles were swallowed by the plant protoplasts, which are a type of spherical plant cells without cell walls.

Most plant transformation, however, occurs with the use of a gene gun, not through endocytosis. In order to use the gene gun to introduce the nanoparticles to walled plant cells, the chemists made another clever modification on the particle surface. They synthesized even smaller gold particles to cap the nanoparticles. These "golden gates" not only prevented chemical leakage, but also added weight to the nanoparticles, enabling their delivery into the plant cell with the standard gene gun.

The biologists successfully used the technology to introduce DNA and chemicals to Arabidopsis, tobacco and corn plants.